<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<style type="text/css" style="display:none;"> P {margin-top:0;margin-bottom:0;} </style>
</head>
<body dir="ltr">
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Hello Saba,</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Where in the load-lock did you find this material? Widely, uniformly distributed, or in spots/patches?</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
What kind of system is this? This is a system to which students/users have access?
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
In our systems, the most popular material to gunk up load-locks with is silicone heat-sink paste (sticking wafer coupons to carrier wafers), which falls neatly into the white, greasy, soft category. The "right" kind of paste has pretty low vapor pressure,
but perhaps a users found some other stuff...<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
If Waterloo has an SEM imaging lab, I'd think the quickest route would be to put this stuff under an EDX analyzer (assuming the SEM folks don't mind some sticky stuff in their chamber).</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
XRF is good for analyzing stuff that you don't want to put into a vacuum. Most uni's that have nanofab core centers will have analytical gear like this.</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
For outside companies, Evans Analytical (EAG now) does this kind of work, but it tends to be kind of expensive.</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Mac Hathaway</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Senior Process and Systems Engineer<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Harvard CNS<br>
</div>
<div id="appendonsend"></div>
<hr style="display:inline-block;width:98%" tabindex="-1">
<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> labnetwork <labnetwork-bounces@mtl.mit.edu> on behalf of Saba Sadeghi <saba.sadeghi@uwaterloo.ca><br>
<b>Sent:</b> Monday, April 12, 2021 10:37 AM<br>
<b>To:</b> labnetwork@mtl.mit.edu <labnetwork@mtl.mit.edu><br>
<b>Subject:</b> [labnetwork] ICP analysis for unknown grease</font>
<div> </div>
</div>
<div class="BodyFragment"><font size="2"><span style="font-size:11pt;">
<div class="PlainText">Dear colleagues,<br>
<br>
I have found a an unknown contamination in the loadlock of our the UHV system. It has a white, greasy, soft texture. I'd like to know the elemental analysis of it since after wiping the system with IPA and baking it the vacuum didn't improve and I am afraid
it must have left residuals. <br>
Would you know any company that offers elemental analysis/ ICP to identify unknown substances?<br>
<br>
Thank you,<br>
Saba <br>
<br>
--<br>
Saba Sadeghi, PhD<br>
Quantum Devices Fabrication Scientist<br>
Email: saba.sadeghi@uwaterloo.ca<br>
_______________________________________________<br>
labnetwork mailing list<br>
labnetwork@mtl.mit.edu<br>
<a href="https://mtl.mit.edu/mailman/listinfo.cgi/labnetwork">https://mtl.mit.edu/mailman/listinfo.cgi/labnetwork</a><br>
</div>
</span></font></div>
</body>
</html>